Circuitry for interfacing a microprocessor with a load for both controlling energization of the load and monitoring the condition of the load is well known in the art. In general such circuitry includes a power transistor for connecting and disconnecting the load with a source of voltage, and further including monitoring circuitry for sensing circuit conditions One of the problems with the prior art approach is that separate I/O pins on the microprocessor chip are employed, one for controlling the load and the other for monitoring the load. See for example U.S. Pat. No. 5,119,312. The approach requires software routines to protect driver in the event of a load short circuit. Furthermore, as the number of loads increases, a point is reached where either a more expensive microprocessor with additional I/O pins is required, or a costly serial peripheral interface (SPI) circuit is used.